Chemical and sensory perception of robusta coffees under wet processing


  • Emanuele Catarina da Silva Oliveira Instituto Federal de Educação, Ciência e Tecnologia, Venda Nova do Imigrante, ES.
  • Rogério Vinícius Carvalho Guarçoni Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural/INCAPER, Departamento de Estatística, Vitória, ES.
  • Eustáquio Vinícius Ribeiro de Castro Universidade Federal do Espírito Santo/UFES, Departamento de Química, Vitória, ES.
  • Marina Gomes de Castro Federal Institute of Education Science and Technology of Espírito Santo
  • Lucas Louzada Pereira Instituto Federal de Educação, Ciência e Tecnologia, Venda Nova do Imigrante, ES.



Robusta Coffee, Infrared Spectroscopy, Chemometrics, Fermentation, Acidity


The quality of the coffee is determined by the sensorial analysis, using subjective methods and it is known that this quality is related to the chemical constituents of the grains. The present study used infrared spectroscopy to correlate the chemical composition of the grain with the final quality of the product and to assist in the current evaluation method, generating more reliability in the process. This study applied the spontaneous and induced fermentation
with starter cultures (yeast) to evaluate the sensory potential from the impacts generated by the types of processes adopted. The experiments were conducted in a randomized block design with five replicates, in a 3x4 factorial scheme, with three fermentation times: 24, 48, and 72 hours and four
wet processes: Washed, Yeast fermentation, Fully washed without yeast, and Fully washed with yeast. Infrared spectra were taken in the medium region
(FTIR-ATR) of the 34 samples generated by the treatments. Given that the method of determining the quality of coffee is subjective, based on scores given by cuppers, the FTIR-ATR spectra were used in the construction of chemometric models to predict sensory ratings given to the attribute ‘acidity’. The
mean error of prediction of the model constructed for the sensory score was 0.11. Sensory results indicated a higher score for the acidity attribute, in dry fermentation with yeast at the time of 48 hours, suggesting a new strategy for the production of quality robusta coffee.
Key words: Fourier transform infrared spectroscopy; chemometrics; fermentation; acidity.

Author Biographies

Emanuele Catarina da Silva Oliveira, Instituto Federal de Educação, Ciência e Tecnologia, Venda Nova do Imigrante, ES.

Food Science and Technology Program

Rogério Vinícius Carvalho Guarçoni, Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural/INCAPER, Departamento de Estatística, Vitória, ES.

Department of Statistics

Eustáquio Vinícius Ribeiro de Castro, Universidade Federal do Espírito Santo/UFES, Departamento de Química, Vitória, ES.

Center of Competence in Petroleum Chemistry-NCQP, Laboratory of Research and Development of Methodologies for Analysis of Oils-LabPetro

Marina Gomes de Castro, Federal Institute of Education Science and Technology of Espírito Santo

Food Science and Technology Program

Lucas Louzada Pereira, Instituto Federal de Educação, Ciência e Tecnologia, Venda Nova do Imigrante, ES.

Coffee analysis and research laboratory


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How to Cite

DA SILVA OLIVEIRA, E. C.; CARVALHO GUARÇONI, R. V.; RIBEIRO DE CASTRO, E. V.; GOMES DE CASTRO, M.; LOUZADA PEREIRA, L. Chemical and sensory perception of robusta coffees under wet processing. Coffee Science - ISSN 1984-3909, v. 15, p. e151672, 11 Aug. 2020.